Aqueous polyurethane resin dispersion composition

Abstract

To provide an aqueous polyurethane resin dispersion composition capable of forming a coating film excellent in alcohol resistance.SOLUTION: The aqueous polyurethane resin dispersion composition contains a polyurethane resin (A), a curing agent (B), an amine compound (C), a film-forming aid (D), and an aqueous medium. The curing agent (B) is a polyisocyanate compound. The amine compound (C) is an amine compound (excluding tertiary amide compounds) having a boiling point of 100°C or higher and having no active hydrogen. The film-forming aid (D) is at least one selected from the group consisting of cyclic amide compounds and cyclic urea compounds.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an aqueous polyurethane resin dispersion composition capable of forming a coating film having excellent alcohol resistance. [Background technology]

[0002] Polyurethane resins are widely used as paints, adhesives, fiber processing agents, paper processing agents, inks, coating agents, etc. Aqueous polyurethane resin dispersions, in which polyurethane resins are dispersed in an aqueous medium, are capable of reducing volatile organic compounds compared to conventional solvent-based polyurethanes, and are therefore increasingly being used as environmentally friendly materials to replace solvent-based polyurethanes.

[0003] The solvent-based urethane has good film-forming properties regardless of the heating temperature because the urethane resin is dissolved in a solvent. However, the aqueous polyurethane resin dispersion has a particulate shape, and films are formed by the fusion of particles. This results in inferior film-forming properties compared to the solvent-based urethane, which poses the problem of reduced chemical resistance, particularly alcohol resistance, of the resulting coating film.

[0004] In order to improve the above performance, various types of aqueous polyurethane resin dispersions have been developed. For example, Patent Document 1 reports that the chemical resistance of the resulting coating film is improved by using a polycarbonate polyol having an alicyclic structure as a raw material polyol for the polyurethane resin.

[0005] Furthermore, as in Patent Document 2, for example, it is known that a building sheet formed using an aqueous adhesive containing a hydroxyl group-containing polyurethane resin having a structure derived from polycarbonate polyol that is liquid at 20°C and a curing agent exhibits excellent adhesion, water resistance, heat resistance, and weather resistance.

[0006] Furthermore, as shown in Patent Document 3, for example, it is known that a coating film obtained from an aqueous coating composition containing a polyurethane resin having a structure derived from polycarbonate polyol, an acrylic resin, and a curing agent exhibits excellent solvent swelling resistance. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 6-248046 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-156573 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-26421 Summary of the Invention [Problem to be solved by the invention]

[0008] Although Patent Document 1 discloses acid resistance and alkali resistance, it does not disclose alcohol resistance, and therefore the effect on alcohol resistance is unclear. Patent Document 2 evaluates a building sheet formed using a water-based adhesive containing urethane, but the alcohol resistance of the urethane coating is unclear. Urethanes generally tend to be corroded by alcohol, and urethane coatings are not compatible with alcohols used for disinfection, for example. Therefore, there is a demand for urethane coatings that are alcohol-resistant. In Patent Document 3, not only the urethane resin synthesis process but also a separate acrylic monomer polymerization process is required, which causes a problem of a heavy burden on the manufacturing process. Also, it was unclear whether a coating film with excellent alcohol resistance could be formed.

[0009] An object of the present invention is to solve the above-mentioned problems in the prior art and to provide an aqueous polyurethane resin dispersion composition capable of forming a coating film having excellent alcohol resistance. [Means for solving the problem]

[0010] The present inventors have conducted various investigations to overcome the problems of the prior art. As a result, they have found that a coating film formed from an aqueous polyurethane resin dispersion composition comprising a polyurethane resin (A), a curing agent (B), an amine compound (C), a coalescing agent (D), and an aqueous medium, wherein the curing agent (B) is a polyisocyanate compound, the amine compound (C) is an amine compound having a boiling point of 100°C or higher and having no active hydrogen (excluding tertiary amide compounds), and the coalescing agent (D) is at least one selected from the group consisting of pyrrolidone compounds and cyclic urea compounds, has good alcohol resistance, and have arrived at the present invention.

[0011] Specifically, the present invention is as follows. (1) A first invention is an aqueous polyurethane resin dispersion composition comprising a polyurethane resin (A), a curing agent (B), an amine compound (C), a coalescing agent (D), and an aqueous medium, wherein the curing agent (B) is a polyisocyanate compound, the amine compound (C) is an amine compound having a boiling point of 100°C or higher and having no active hydrogen (excluding tertiary amide compounds), and the coalescing agent (D) is at least one selected from the group consisting of cyclic amide compounds and cyclic urea compounds. (2) A first invention is the aqueous polyurethane resin dispersion composition according to (1) above, wherein the main chain of the polyurethane resin (A) has a structure derived from a polycarbonate polyol (Aa) having an alicyclic structure, a structure derived from a polyisocyanate (Ab), and a structure derived from an acidic group-containing polyol (Ac). (3) A third invention is the aqueous polyurethane resin dispersion composition according to (1) or (2), wherein the content of the alicyclic structure in the polycarbonate polyol (Aa) having an alicyclic structure is 20 to 50 mass% based on the total amount of the polycarbonate polyol (Aa). (4) A fourth invention is the aqueous polyurethane resin dispersion composition according to any one of (1) to (3), wherein the content of the alicyclic structure in the polyurethane resin (A) is 20 to 70 mass % based on the solid content. (5) A fifth invention is the aqueous polyurethane resin dispersion composition according to any one of (1) to (4) above, wherein the polyurethane resin (A) has a hydroxyl value of 3.0 to 15 mgKOH / g. (6) A sixth invention is the aqueous polyurethane resin dispersion composition according to any one of (1) to (5) above, wherein the curing agent (B) is a linear aliphatic polyisocyanate compound. (7) A seventh invention is the aqueous polyurethane resin dispersion composition according to any one of (1) to (6) above, wherein the amine compound (C) is a heterocyclic aliphatic tertiary amine compound. (8) An eighth invention is the aqueous polyurethane resin dispersion composition according to any one of (1) to (7) above, which contains 0.30 to 3.0 mass % of the amine compound (C) relative to the polyurethane resin (A). (9) A ninth invention is the aqueous polyurethane resin dispersion composition according to any one of (1) to (8) above, wherein the film-forming aid (D) is a pyrrolidone compound. (10) A tenth invention is the aqueous polyurethane resin dispersion composition according to any one of (1) to (9) above, which contains 15 to 40 mass % of the film-forming aid (D) relative to the polyurethane resin (A). (11) An eleventh invention is a coating composition containing the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above. (12) A twelfth aspect of the present invention is a coating agent composition containing the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above. (13) A thirteenth invention is a floor coating agent containing the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above. (14) A fourteenth invention is a plastic coating agent containing the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above. (15) A fifteenth aspect of the present invention is a steel plate treatment agent containing the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above. (16) A sixteenth invention is a primer containing the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above. (17) A seventeenth aspect of the present invention is a base coating agent containing the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above. (18) An eighteenth invention is a method for producing a coating film, comprising a step of applying the aqueous polyurethane resin dispersion composition according to any one of (1) to (10) above and then drying the applied composition. (19) A nineteenth invention is the method for producing a coating film according to (18) above, wherein the drying is carried out at 20 to 100°C. (20) A twentieth invention is a coating film obtained by the manufacturing method described in (18) or (19) above. (21) The twenty-first invention is the use of the coating film according to (20) above as a floor coat, a coat for plastic or rubber, a steel plate treatment agent, or a primer or base coat for metal exteriors. [Effects of the Invention]

[0012] According to the present invention, there is provided an aqueous polyurethane resin dispersion composition capable of forming a coating film having excellent alcohol resistance. DETAILED DESCRIPTION OF THE INVENTION

[0013] The aqueous polyurethane resin dispersion composition of the present invention comprises a polyurethane resin (A), a curing agent (B), an amine compound (C), a coalescing agent (D), and an aqueous medium, wherein the curing agent (B) is a polyisocyanate compound, the amine compound (C) is an amine compound (excluding tertiary amide compounds) having a boiling point of 100°C or higher and having no active hydrogen, and the coalescing agent (D) is at least one selected from the group consisting of cyclic amide compounds and cyclic urea compounds. Unless otherwise specified, the boiling point refers to the boiling point at atmospheric pressure. Each component constituting the aqueous polyurethane resin dispersion composition of the present invention will be described in detail below.

[0014] <Polyurethane resin (A)> The polyurethane resin (A) (hereinafter sometimes referred to as "(A)") used in the composition of the present invention is a polymer having a urethane bond as a repeating unit. It is generally composed of a combination of a structure derived from a polyol and a structure derived from a polyisocyanate. The components of (A) used in the composition of the present invention are not limited to the type of compound from which they are derived, as long as they are dispersible in water. Dispersibility in water can be achieved, for example, by using a compound that allows polar groups to be present when the polyurethane resin is formed. More specifically, the polyurethane resin (A) has a structure derived from a polycarbonate polyol (Aa), a structure derived from a polyisocyanate (Ab), and a structure derived from an acidic group-containing polyol (Ac). The polyurethane resin (A) or the components from which each of its structural units is derived may be known, and its manufacturing method is not limited. Furthermore, the polyurethane resin (A) may also have a structure derived from a hydroxyl group-containing polyamine (Ad), a chain extender (Ae), a polyol (Af) other than (Aa), or a neutralizer (Ag).

[0015] (Polycarbonate polyol (Aa)) The polyurethane resin (A) preferably has a structural unit derived from a polycarbonate polyol (Aa), and more preferably has a structural unit derived from a polycarbonate polyol (Aa) having an alicyclic structure. The polycarbonate polyol (Aa) is obtained by reacting a polyol monomer containing at least one polyol component with a carbonate source compound such as a carbonate ester or phosgene. From the standpoints of safety and reagent handling, etc., ease of production and the absence of by-products of terminal chlorinated products, polycarbonate polyols obtained by reacting a polyol monomer containing at least one polyol component having an alicyclic structure with a carbonate ester are preferred.

[0016] At least a portion of the polyol monomers constituting the polycarbonate polyol (Aa) preferably has an alicyclic structure. The content of the alicyclic structure is not particularly limited, but is preferably 1 to 55 mass %, more preferably 20 to 50 mass %, and even more preferably 25 to 40 mass %, based on the total amount of the polycarbonate polyol (Aa). When the content of the alicyclic structure is within the above range, a coating film having excellent hardness and adhesion and improved alcohol resistance is obtained, which is preferable. The content of the alicyclic structure refers to the content of cyclohexane residues, for example, when the structure contains a cyclohexane ring, and also refers to the content of cyclohexane residues in the case of a compound in which a cyclohexane ring is not arranged in the main chain when the compound is made into a polycarbonate polyol. When a substituent is bonded to the cyclohexane ring, the cyclohexane residue refers to the structure of the cyclohexane ring excluding the substituent. In other words, the structure calculated as the content of the alicyclic structure is the portion consisting of carbon atoms forming the ring structure and hydrogen atoms directly bonded thereto.

[0017] As the polyol monomer having an alicyclic structure constituting the polycarbonate polyol (Aa) having an alicyclic structure, known ones can be used. Among them, it is preferable to use a polyol monomer containing a cyclohexane ring as the alicyclic structure from the viewpoint of hardness and alcohol resistance when formed into a coating film. Specific examples of polyol monomers having an alicyclic structure include 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,3-cyclopentanediol, 1,4-cycloheptanediol, 2,5-bis(hydroxymethyl)-1,4-dioxane, 2,7-norbornanediol, tetrahydrofuran dimethanol, and 1,4-bis(hydroxyethoxy)cyclohexane.

[0018] As the polyol monomer having an alicyclic structure constituting the polycarbonate polyol (Aa) having an alicyclic structure, 1,4-cyclohexanedimethanol can be suitably used from the viewpoint of improving alcohol resistance.

[0019] The polycarbonate polyol (Aa) having an alicyclic structure may contain, as a constituent component, a polyol having no alicyclic structure in addition to the polyol monomer having an alicyclic structure. The polyol having no alicyclic structure is not particularly limited, and examples thereof include aliphatic polyols such as linear aliphatic diols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, and 1,9-nonanediol, branched aliphatic diols such as 2-methyl-1,3-propanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,5-hexanediol, and 2-methyl-1,8-octanediol, trifunctional or higher polyhydric alcohols such as trimethylolpropane and pentaerythritol; 1,4-benzenedimethanol, 1,3-benzenedimethanol, and 1,8-octanediol. Examples include aromatic diols such as 2-benzenedimethanol, 4,4'-naphthalenedimethanol, and 3,4'-naphthalenedimethanol; polyester polyols of hydroxycarboxylic acids and diols such as polyester polyols of 6-hydroxycaproic acid and hexanediol; polyester polyols of dicarboxylic acids and diols such as polyester polyols of adipic acid and hexanediol; and polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.Aliphatic polyols are preferred, linear aliphatic diols are more preferred, and 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol are even more preferred. The polycarbonate polyol (Aa) having no alicyclic structure can contain the above-mentioned polyol having no alicyclic structure as a constituent component.

[0020] The polyol monomers of the polycarbonate polyol (Aa) having an alicyclic structure may be used alone or in combination of two or more kinds.

[0021] The carbonate ester is not particularly limited, and examples thereof include aliphatic carbonate esters such as dimethyl carbonate and diethyl carbonate; aromatic carbonate esters such as diphenyl carbonate; and cyclic carbonate esters such as ethylene carbonate. In addition, phosgene, which can produce polycarbonate polyol, can also be used. Among these, aliphatic carbonate esters are preferred, and dimethyl carbonate is more preferred, in view of the ease of producing the polycarbonate polyol (Aa).

[0022] The polycarbonate polyol (Aa) may contain ether bonds or ester bonds in its molecule in a number less than the average number of carbonate bonds in one molecule, as long as the properties of the polycarbonate polyol are not impaired.

[0023] The polycarbonate polyol (Aa) having an alicyclic structure preferably has a number average molecular weight (Mn) of 400 to 5,000. When Mn is 400 or more, the performance as a soft segment is good, and cracks are less likely to occur when a coating film is formed. When Mn is 5,000 or less, the reactivity of the polycarbonate polyol (Aa) having an alicyclic structure with the polyisocyanate (Ab) does not decrease, and problems such as the urethane prepolymer production process taking a long time, the reaction not proceeding sufficiently, and the viscosity of the polycarbonate polyol becoming high and making it difficult to handle do not occur. The Mn of the polycarbonate polyol (Aa) having an alicyclic structure is preferably 500 to 3,500, more preferably 600 to 2,500. In the present invention, Mn is determined by the hydroxyl value and 1 The value is calculated from the quantitative value of the composition by H-NMR or gas chromatography after alkaline hydrolysis.

[0024] (Polyisocyanate (Ab)) The polyurethane resin (A) has a structural unit derived from a polyisocyanate (Ab). Known polyisocyanates can be used as the polyisocyanate (Ab). For example, aromatic isocyanate compounds such as 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, and 4,4'-diphenylmethane diisocyanate (MDI) can be used; and aliphatic isocyanates such as ethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate (PDI), and hexamethylene diisocyanate (HDI) can be used. Examples of suitable polyisocyanate compounds include alicyclic isocyanate compounds such as isophorone diisocyanate (IPDI), 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis(2-isocyanatoethyl)-4-dicyclohexene-1,2-dicarboxylate, 2,5-norbornane diisocyanate, and 2,6-norbornane diisocyanate. The polyisocyanate (Ab) may have a structure whose entirety or part has been derivatized by isocyanuration, carbodiimidization, biuretization, or the like.

[0025] Among the polyisocyanates (Ab), aromatic isocyanate compounds and alicyclic isocyanate compounds are preferred from the viewpoint of controlling reactivity, and isophorone diisocyanate (IPDI), 4,4'-diphenylmethane diisocyanate (MDI), and 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI) are more preferred from the viewpoint of improving alcohol resistance. The polyisocyanates (Ab) may be used alone or in combination of two or more kinds.

[0026] The polyisocyanate (Ab) is preferably at least one selected from the group consisting of isophorone diisocyanate, 4,4'-diphenylmethane diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate.

[0027] The amount of polyisocyanate (Ab) used is such that the ratio of isocyanate groups in the polyisocyanate (Ab) to hydroxyl groups derived from all polyols (isocyanate groups / hydroxyl groups (molar ratio)) is preferably in the range of 0.3 to 5.0, more preferably in the range of 0.5 to 3.0, still more preferably in the range of 0.9 to 2.5, and particularly preferably in the range of 1.2 to 2.0. The polyol is the total of the polycarbonate polyol (Aa), the acidic group-containing polyol (Ac) described below, and the other polyols (Af) described below.

[0028] (Acidic group-containing polyol (Ac)) The polyurethane resin (A) preferably contains a structural unit derived from an acidic group-containing polyol (Ac) in order to improve dispersibility in water. The acidic group-containing polyol (Ac) contains two or more hydroxyl groups and one or more acidic groups in one molecule. One type of acidic group-containing polyol (Ac) may be used alone, or multiple types may be used in combination.

[0029] Known acidic group-containing polyols (Ac) can be used. Examples include dimethylolalkanoic acids such as 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid; N,N-bishydroxyethylglycine, N,N-bishydroxyethylalanine, 3,4-dihydroxybutanesulfonic acid, and 3,6-dihydroxy-2-toluenesulfonic acid. Among these, from the viewpoint of availability, dimethylolalkanoic acids having 4 to 12 carbon atoms and two methylol groups are preferred, and among dimethylolalkanoic acids, 2,2-dimethylolpropionic acid is more preferred.

[0030] (Hydroxyl-containing polyamine (Ad)) The polyurethane resin (A) may have a structural unit derived from a hydroxyl group-containing polyamine (Ad). By introducing the hydroxyl group-containing polyamine (Ad) into the polyurethane resin (A), the molecular weight is increased and further hydroxyl groups are imparted.

[0031] The hydroxyl group-containing polyamine (Ad) contains one or more hydroxyl groups (excluding phenolic hydroxyl groups) and two or more amino groups and / or imino groups in one molecule, and known compounds can be used. Such compounds are preferably alkanol polyamines excluding tertiary amines, and specific examples include aromatic alkanol diamines such as 3,5-diaminobenzyl alcohol, and aliphatic alkanol polyamines such as 1,3-diamino-2-propanol, 2,2'-(ethylenebisimino)bisethanol, N-(2-hydroxyethyl)-N'-(2-aminoethyl)ethylenediamine, N-(3-hydroxypropyl)ethylenediamine, 2-[bis(2-aminoethyl)amino]ethanol, 1-[2-[(2-aminoethyl)amino]ethyl]amino-2-propanol, N,N-bis(hydroxyethyl)diethylenetriamine, N1,N4-bis(hydroxyethyl)diethylenetriamine, N1-(2-hydroxypropyl)triethylenetetraamine, N4-(2-hydroxypropyl)triethylenetetraamine, N-(2-hydroxypropyl)triethylenetetraamine, and 2-(2-aminoethylamino)ethanol.

[0032] As the hydroxyl group-containing polyamine (Ad), it is preferable to use an aliphatic alkanol polyamine, and it is more preferable to use 2-(2-aminoethylamino)ethanol, from the viewpoints of ease of synthesis of the polyurethane resin (A), ease of imparting hydroxyl groups to the polyurethane resin (A), and improvement of the alcohol resistance of the coating film of the present invention.

[0033] The hydroxyl group-containing polyamine (Ad) may be used alone or in combination of two or more kinds.

[0034] (Chain extender (Ae)) The polyurethane resin (A) may contain structural units derived from a chain extender (Ae) to increase the molecular weight. The chain extender (Ae) is a compound other than the polycarbonate polyol (Aa), the acidic group-containing polyol (Ac), the hydroxyl group-containing polyamine (Ad), and the other polyol (Af) described below, and is reactive with the isocyanato group of the polyurethane prepolymer.

[0035] The chain extender (Ae) may be a known one, such as amine compounds such as ethylenediamine, 1,4-tetramethylenediamine, 2-methyl-1,5-pentanediamine, 1,4-butanediamine, 1,6-hexamethylenediamine, 1,4-hexamethylenediamine, 3-aminomethyl-3,5,5-trimethylcyclohexylamine, 1,3-bis(aminomethyl)cyclohexane, xylylenediamine, piperazine, 2,5-dimethylpiperazine, diethylenetriamine, and triethylenetetramine, or water, with amine compounds being preferred.

[0036] Among the chain extenders (Ae), polyamines with a number average molecular weight (Mn) of 300 or less are preferred. An Mn of 300 or less is advantageous because it can further increase the cohesive strength of the polyurethane resin. In addition, the use of polyamines with two or more functional groups in one molecule is preferred because it can increase the Mn of the polyurethane resin and improve its durability. Among the chain extenders (Ae), those having a number average molecular weight (Mn) of 18 or more are preferred, and polyamines having an Mn of 60 or more are preferred.

[0037] The chain extender (Ae) may be used alone or in combination of two or more kinds.

[0038] (Amounts of hydroxyl-containing polyamine (Ad) and chain extender (Ae) used) When a hydroxyl-containing polyamine (Ad) and a chain extender (Ae) are used, the total amount used is preferably equal to or less than the equivalent of the isocyanato group that serves as the chain extension initiation point in the polyurethane prepolymer, which is a synthetic intermediate of the polyurethane resin (A), and more preferably 0.70 to 0.99 equivalents of the isocyanato group in the polyurethane prepolymer. Adding the hydroxyl-containing polyamine (Ad) and the chain extender (Ae) in an amount equal to or less than the equivalent of the isocyanato group in the polyurethane prepolymer tends to increase the strength of the coating film without decreasing the molecular weight of the chain-extended polyurethane resin (A). The hydroxyl group-containing polyamine (Ad) is preferably used so that the hydroxyl group value of the polyurethane resin (A) falls within the range of 3.0 to 15 mgKOH / g. The specific amount of the hydroxyl group-containing polyamine (Ad) used is preferably 0.1 to 10 mass%, more preferably 0.3 to 7.0 mass%, and even more preferably 0.5 to 5.0 mass%, based on the total solid content of the polycarbonate polyol (Aa), polyisocyanate (Ab), and acidic group-containing polyol (Ac). When the chain extender (Ae) is used, the amount of the chain extender (Ae) added is preferably 0.1 to 15 mass %, more preferably 0.1 to 10 mass %, based on the total solid content of the polycarbonate polyol (Aa), the polyisocyanate (Ab), and the acidic group-containing polyol (Ac).

[0039] (Polyol (Af) other than (Aa) and (Ac)) The polyurethane resin (A) may have structural units derived from a polyol (Af) other than the polycarbonate polyol (Aa) and the acidic group-containing polyol (Ac). Other polyols (Af) that can be used include known polyols, such as polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, random copolymers or block copolymers of ethylene oxide and propylene oxide, or ethylene oxide and butylene oxide; aliphatic diols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 3-methyl-1,5-pentanediol, and 2-butyl-2-ethyl-1,3-propanediol; alicyclic diols such as 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and hydrogenated bisphenol A; 1,4-benzenedimethanol, 1,3-benzenedimethanol, and 1,2-benzenediol; Examples of polyester polyols include aromatic diols such as methanol, 4,4'-naphthalenedimethanol, and 3,4'-naphthalenedimethanol; trifunctional or higher polyhydric alcohols such as trimethylolpropane and pentaerythritol; diols such as bisphenol A, hydroquinone, bishydroxyethoxybenzene, and alkylene oxide adducts thereof; and polyester polyols obtained from the above-mentioned polycarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalic acid, 2,6-naphthalic acid, 4,4'-diphenyldicarboxylic acid, 2,2'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, trimellitic acid, pyromellitic acid, adipic acid, azelaic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, dodecanedicarboxylic acid, dimer acid, and hydrogenated dimer acid. In addition, when the polycarbonate polyol (Aa) has an alicyclic structure, examples thereof include polycarbonate polyols having no alicyclic structure, which are composed of the above polyols having no alicyclic structure. The other polyol compound (Af) is preferably contained in an amount of less than 70 mass%, more preferably less than 60 mass%, even more preferably less than 50 mass%, and particularly preferably less than 40 mass%, based on the total amount of the polyol compounds (Aa), (Ac), and (Af). Those skilled in the art can appropriately adjust the type and amount of the other polyol compound (Af) depending on the physical properties desired for the aqueous polyurethane resin, within a range that does not impair the effects of the present invention, but the other polyol compound (Af) does not necessarily need to be contained in the polyurethane resin (A).

[0040] In the polyurethane resin (A), the total hydroxyl equivalent number of the polycarbonate polyol (Aa), the acidic group-containing polyol (Ac), and the other polyol (Af) is preferably 50 to 4,000. If the hydroxyl equivalent number is within this range, production of an aqueous polyurethane resin dispersion containing the obtained polyurethane resin is easy. From the viewpoint of the storage stability of the obtained aqueous polyurethane resin dispersion, the hydroxyl equivalent number is preferably 100 to 3,500, more preferably 120 to 3,000, and even more preferably 130 to 2,500. The acidic group-containing polyol (Ac) and the other polyol (Af) can be used in any amounts as long as the above-mentioned range is achieved, but the total amount of the acidic group-containing polyol (Ac) and the other polyol (Af) used is preferably less than 80 mass% based on the total amount of the polyol compounds (Aa), (Ac), and (Af).

[0041] The hydroxyl group equivalent number can be calculated by the following formulas (1) and (2). Hydroxyl equivalent weight of each polyol component = molecular weight of each polyol component / number of hydroxyl groups of each polyol component (1) Total hydroxyl equivalents of polyol components = M / total moles of polyol components (2) In formula (2), M represents [[hydroxyl group equivalent number of polycarbonate polyol component × number of moles of polycarbonate polyol component] + [hydroxyl group equivalent number of acidic group-containing polyol × number of moles of acidic group-containing polyol] + [hydroxyl group equivalent number of other polyol × number of moles of other polyol]].

[0042] (Neutralizer (Ag)) The polyurethane resin (A) may have a structural unit derived from a neutralizing agent (Ag) in order to neutralize the acidic groups. The neutralizing agent (Ag) may be used alone or in combination of two or more types.

[0043] Known neutralizing agents (Ag) can be used, including organic amines such as trimethylamine, triethylamine, triisopropylamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-phenyldiethanolamine, 2-dimethylaminoethanol, 2-(dimethylamino)-2-methyl-1-propanol, diethylethanolamine, and pyridine; inorganic alkalis such as sodium hydroxide and potassium hydroxide; and ammonia.

[0044] The neutralizing agent (Ag) preferably has a boiling point of 200°C or lower, more preferably in the range of -50 to 180°C, in order to obtain even better adhesive strength at the temperature (usually 50 to 180°C) when drying the aqueous medium in the aqueous polyurethane resin dispersion composition.When a dried coating film is obtained in a short time of several seconds to 1 hour at a low temperature of 100°C or lower, the boiling point is preferably 130°C or lower, more preferably 100°C or lower.

[0045] When a neutralizing agent (Ag) is used, the amount used is preferably in the range of 0.8 to 2.0 times the number of moles of the acidic groups contained in the polyurethane resin (A). When the amount of the neutralizing agent (Ag) used is 0.8 times or more the number of moles of the acidic groups contained in the aqueous polyurethane resin dispersion, the stability of the resulting dispersion is high, and when it is 2.0 times or less, a coating film with high substrate adhesion can be obtained in a short time of several seconds to 1 hour under low-temperature drying at 100°C or less.

[0046] (Method for producing aqueous polyurethane resin dispersion) Next, a method for producing an aqueous polyurethane resin dispersion will be described. The aqueous polyurethane resin dispersion has a polyurethane resin (A) dispersed in an aqueous medium. The method for producing an aqueous polyurethane resin dispersion includes dispersing a polyurethane prepolymer obtained by reacting a polyol with a polyisocyanate, the polyurethane prepolymer containing a compound having a polar group that imparts water dispersibility, in an aqueous medium. More specifically, the method includes the following steps: (I) a step of reacting the polycarbonate polyol (Aa), the polyisocyanate (Ab), the acidic group-containing polyol (Ac), and optionally a polyol (Af) other than (Aa) and (Ac) to obtain a polyurethane prepolymer; (II) neutralizing the acidic groups of the polyurethane prepolymer with a neutralizing agent (Ag); (III) dispersing the polyurethane prepolymer in an aqueous medium; and (IV) A step of reacting the polyurethane prepolymer with a hydroxyl group-containing polyamine (Ad) reactive with the isocyanato group of the polyurethane prepolymer, and a chain extender (Ae). Furthermore, when an organic solvent is used in step (I), step (V) may include a step of removing the organic solvent. The aqueous polyurethane resin dispersion of the present invention can be produced by a known method described in known documents (for example, WO 2016 / 039396, WO 2016 / 163394, etc.).

[0047] In the step (II), only when an amine compound (C) described below is added, the amine compound (C) can also serve as the neutralizing agent (Ag).

[0048] (Polyurethane prepolymer) In the step (I), the polyurethane prepolymer is obtained by reacting a polycarbonate polyol (Aa), a polyisocyanate (Ab), an acidic group-containing polyol (Ac), and a polyol (Af) other than (Aa) and (Ac). Thus, the polyurethane prepolymer has at least a structure derived from the polycarbonate polyol (Aa), a structure derived from the polyisocyanate (Ab), and a structure derived from the acidic group-containing polyol (Ac), and optionally has a structure derived from the other polyol (Af).

[0049] The blending amount of each raw material in the polyurethane prepolymer is preferably selected within a range in which the content of free isocyanato groups is 0.5 to 5.0 mass% based on the solid content of the polyurethane prepolymer, as this provides good dispersibility in water.

[0050] The acid value (AV) of the polyurethane prepolymer is preferably 4 to 40 mgKOH / g, more preferably 6 to 32 mgKOH / g, and even more preferably 8 to 29 mgKOH / g. By making the acid value of the polyurethane prepolymer 4 mgKOH / g or more, it tends to be possible to improve dispersibility in aqueous media and storage stability. Furthermore, by making the acid value of the polyurethane prepolymer 40 mgKOH / g or less, it tends to be possible to improve the water resistance of the polyurethane resin coating film and increase the flexibility of the resulting film. It also tends to be possible to improve the drying properties of the coating film during production.

[0051] The "acid value of the polyurethane prepolymer" refers to the acid value of the so-called solid content, excluding the solvent used in producing the polyurethane prepolymer and the neutralizing agent used to disperse the polyurethane prepolymer in an aqueous medium.

[0052] Specifically, the acid value of the polyurethane prepolymer can be calculated by the following formula (3). [Acid value of polyurethane prepolymer] = [(number of millimoles of acidic group-containing polyol) × (number of acidic groups in one molecule of acidic group-containing polyol) + (number of millimoles of hydroxyalkanoic acid) × (number of acidic groups in one molecule of hydroxyalkanoic acid)] × 56.1 / [total mass of polyisocyanate, acidic group-containing polyol, hydroxyalkanoic acid, blocking agent, polycarbonate polyol, and other polyols] (3)

[0053] (Aqueous polyurethane resin dispersion) The proportion of the polyurethane resin (A) in the aqueous polyurethane resin dispersion is 5 to 60% by mass, preferably 20 to 50% by mass.

[0054] The hydroxyl value of the polyurethane resin (A) in the aqueous dispersion is not particularly limited, but is preferably 0 to 20 mgKOH / g, more preferably 3.0 to 15 mgKOH / g from the viewpoint of improving the alcohol resistance of the coating film obtained from the aqueous polyurethane resin dispersion composition, and even more preferably 4.0 to 13 mgKOH / g from the viewpoint of storage stability. The hydroxyl value is the number of milligrams (mg) of potassium hydroxide equivalent to the hydroxyl groups in 1 g of sample, and can be measured by Method A of JIS K 1557.

[0055] The weight-average molecular weight (Mw) of the polyurethane resin (A) in the aqueous dispersion is preferably 200,000 to 10,000,000, more preferably 300,000 to 5,000,000, and even more preferably 400,000 to 2,000,000. The weight-average molecular weight is measured by gel permeation chromatography (GPC), and a converted value obtained from a previously prepared calibration curve of standard polystyrene can be used. By setting the weight-average molecular weight to 200,000 or more, a good coating film tends to be obtained. By setting the weight-average molecular weight to 10,000,000 or less, the drying properties of the aqueous polyurethane resin dispersion tend to be improved.

[0056] The content of the alicyclic structure in the polyurethane resin (A) in the aqueous dispersion is preferably 20 to 70 mass% on a solids basis relative to the total amount of the polyurethane resin (A). The content of the alicyclic structure is preferably 30 to 50 mass% on a solids basis, more preferably 32 to 48 mass%, and even more preferably 34 to 46 mass%. A content ratio of the alicyclic structure within the above range is preferable in that it can more effectively suppress a decrease in dispersibility of the aqueous polyurethane resin dispersion, an increase in the median particle size, gelation, hydrolysis, etc. Note that the "content of the alicyclic structure" in the content of the alicyclic structure in the polyurethane resin (A) in the aqueous dispersion refers to the content of the alicyclic structure present in all constituent components of the polyurethane resin (A), such as the polycarbonate polyol (Aa) and polyisocyanate (Ab), in the polyurethane resin (A).

[0057] In the polyurethane resin (A) in the aqueous dispersion, the content of urethane bonds and urea bonds is preferably 7 to 25 mass % on a solids basis, and particularly preferably 8 to 22 mass %.

[0058] The content ratios of urethane bonds and urea bonds can be controlled by the molecular weights of the polyisocyanate (Ab), polycarbonate polyol (Aa), acidic group-containing polyol (Ac), other polyol (Af), and optionally the blocking agent, hydroxyl group-containing polyamine (Ad), and chain extender (Ae), the numbers of hydroxyl groups, isocyanato groups, and amino groups in one molecule, and the proportions of each raw material used on a solids basis in the aqueous polyurethane resin dispersion.

[0059] By setting the content of the urethane bond and urea bond to 7% by mass or more, stickiness of the coating film surface after drying tends to be reduced, and by setting the content of the urethane bond and urea bond to 25% by mass or less, adhesion between the coating film formed from the aqueous polyurethane resin dispersion and the substrate tends to be improved.

[0060] Here, it is clear to a person skilled in the art which raw materials each structure and group, such as carbonate and urethane, in polyurethane is derived from, and furthermore, almost all of the raw materials are incorporated into the polyurethane resin (A) produced, or it is easy to design it so that the contents of alicyclic structures, urethane bonds, urea bonds, etc. in the polyurethane resin (A) can be roughly calculated from the charged amounts, the molecular weights of the respective raw materials, and the molecular weights or number of moles of the portions corresponding to the respective structures.

[0061] The acid value of the polyurethane resin (A) in the aqueous dispersion is not particularly limited, but is preferably 10 to 40 mgKOH / g, more preferably 15 to 32 mgKOH / g, and particularly preferably 17 to 30 mgKOH / g, based on the solids content. Setting the acid value of the polyurethane resin (A) to a range of 10 to 40 mgKOH / g, based on the solids content, tends to improve storage stability. The acid value can be measured in accordance with the indicator titration method of JIS K 1557. The measurement is performed after removing the neutralizing agent used to neutralize the acidic groups. For example, when an organic amine is used as the neutralizing agent, the aqueous polyurethane resin dispersion can be applied to a glass plate and dried at 60°C under a reduced pressure of 20 mmHg for 24 hours. The resulting coating film can then be dissolved in N-methylpyrrolidone (NMP), and the acid value can be measured in accordance with the indicator titration method of JIS K 1557.

[0062] The glass transition temperature (Tg) of the polyurethane resin (A) in the aqueous dispersion is preferably −10° C. or higher, more preferably −10 to 100° C., even more preferably 10 to 90° C., and even more preferably 30 to 80° C. When the Tg of the polyurethane resin (A) is −10° C. or higher, the alcohol resistance is better.

[0063] <Curing agent (B)> The curing agent (B) (hereinafter sometimes referred to as "(B)") used in the aqueous polyurethane resin dispersion composition of the present invention is a polyisocyanate compound. Known polyisocyanate compounds can be used.

[0064] The curing agent (B) is a compound having at least two isocyanate groups in one molecule. For example, the same compounds as those described for the polyisocyanate (Ab) can be used. Among them, aliphatic polyisocyanate compounds and alicyclic polyisocyanate compounds are preferred, and from the viewpoint of improving curing properties at low temperatures, aliphatic polyisocyanate compounds are more preferred, and linear aliphatic polyisocyanate compounds are even more preferred. These may be used alone or in combination.

[0065] The isocyanate group of the polyisocyanate compound may be blocked with a blocking agent. Examples of blocking agents include phenol-based blocking agents such as phenol and cresol, aliphatic alcohol-based blocking agents such as methanol and ethanol, active methylene-based blocking agents such as dimethyl malonate and acetylacetone, mercaptan-based blocking agents such as butyl mercaptan and dodecyl mercaptan, acid amide-based blocking agents such as acetanilide and acetic acid amide, lactam-based blocking agents such as ε-caprolactam and δ-valerolactam, acid imide-based blocking agents such as succinimide and maleimide, oxime-based blocking agents such as acetaldoxime, acetoneoxime, and methylethylketoxime, amine-based blocking agents such as diphenylaniline, aniline, ethyleneimine, and dimethylpyrazole, and hydroxycarboxylic acids such as hydroxypivalic acid and dimethylolpropionic acid. Among these, from the viewpoint of improving the smoothness of the coating film, oxime-based blocking agents, active methylene-based blocking agents, and amine-based blocking agents are preferred, and pyrazole is more preferred.

[0066] The polyisocyanate compound may be a commercially available product, such as the EASAQUA (registered trademark) series manufactured by Vencorex, but is not limited to such examples.

[0067] The mass ratio of the curing agent (B) to the polyurethane resin (A) is preferably (B) / (A)=0.10 to 0.65, more preferably 0.13 to 0.63, from the viewpoint of improving storage stability and alcohol resistance of the coating film.

[0068] <Amine Compound (C)> The amine compound (C) (hereinafter sometimes referred to as "(C)") used in the aqueous polyurethane resin dispersion composition of the present invention is an amine compound (excluding tertiary amide compounds) that has a boiling point of 100°C or higher and does not have active hydrogen. Known amine compounds can be used. The active hydrogen is a hydrogen atom that reacts with an isocyanate group, and examples of the active hydrogen include hydrogen atoms of an amino group, a hydroxyl group, a mercapto group, etc.

[0069] Examples of the amine compound (C) include aliphatic tertiary amine compounds such as tripropylamine, tributylamine, N,N-dimethylcyclohexylamine, and N-methyldicyclohexylamine; N-alkylpolyalkylenepolyamine compounds such as N,N,N',N'-tetramethylethylenediamine and N,N,N',N'-tetramethylhexamethylenediamine; heterocyclic aliphatic tertiary amine compounds such as triethylenediamine, diazabicyclononene, diazabicycloundecene, N-methylmorpholine, N-ethylmorpholine, and dimethylpiperazine; and tertiary amine compounds having an aromatic ring such as 4-dimethylaminopyridine, 1-methylimidazole, and 1,2-dimethylimidazole. Among these, heterocyclic aliphatic tertiary amine compounds are preferred, and triethylenediamine is more preferred, from the viewpoint of catalytic activity. These compounds may be used alone or in combination.

[0070] In the aqueous polyurethane resin dispersion composition of the present invention, the amine compound (C) is contained in an amount of preferably 0.20 to 4.0 mass %, more preferably 0.30 to 3.0 mass %, relative to the polyurethane resin (A) from the viewpoints of improving storage stability and alcohol resistance of the coating film.

[0071] The amine compound (C) is added to the aqueous polyurethane resin dispersion obtained by the steps (I) to (V), but can also be added in the step (II) for obtaining the aqueous polyurethane resin dispersion. The amine compound (C) added in this case can also serve as the neutralizing agent (Ag).

[0072] <Film-forming agent (D)> The film-forming aid (D) (hereinafter sometimes referred to as "(D)") used in the aqueous polyurethane resin dispersion composition of the present invention is at least one selected from the group consisting of cyclic amide compounds and cyclic urea compounds. Known cyclic amide compounds and cyclic urea compounds can be used.

[0073] Examples of the cyclic amide compound used as the film-forming auxiliary (D) include azetidinone compounds such as 2-azetidinone, N-methylazetidinone, and N-ethylazetidinone; pyrrolidone compounds such as 2-pyrrolidone, N-methylpyrrolidone, N-ethylpyrrolidone, N-propylpyrrolidone, N-isopropylpyrrolidone, N-butylpyrrolidone, N-cyclohexylpyrrolidone, N-octylpyrrolidone, N-phenylpyrrolidone, and vinylpyrrolidone; piperidone compounds such as 2-piperidone, N-methylpiperidone, and N-ethylpiperidone; 2-imidazolidinone, 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, 1,3-dipropyl-2-imidazolidinone, and 1,3-dibutyl-2-imidazolidinone. Among these, from the viewpoint of improving film-forming properties, cyclic amide compounds are preferred, pyrrolidone compounds are more preferred, and N-methylpyrrolidone and N-ethylpyrrolidone are even more preferred. These may be used alone or in combination.

[0074] In the aqueous polyurethane resin dispersion composition of the present invention, the film-forming aid (D) is preferably contained in an amount of 10 to 50 mass % relative to the polyurethane resin (A), more preferably 15 to 40 mass %, from the viewpoint of improving the alcohol resistance of the coating film.

[0075] The aqueous polyurethane resin dispersion composition according to the present invention contains an aqueous medium in addition to the polyurethane resin (A), the curing agent (B), the amine compound (C), and the coalescent (D). The aqueous medium is water or a mixed medium of water and a hydrophilic organic solvent excluding the film-forming aid (D). Examples of water include tap water, ion-exchanged water, distilled water, and ultrapure water. Examples of hydrophilic organic solvents excluding the film-forming aid (D) include ketones such as acetone and ethyl methyl ketone; ethers such as diethyl ether and dipropylene glycol dimethyl ether; alcohols such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, and diethylene glycol; linear aliphatic amides such as β-alkoxypropionamide, typified by "KJCMPA(R)-100" manufactured by KJ Chemical Co.; and hydroxyl group-containing tertiary amines such as 2-(dimethylamino)-2-methyl-1-propanol (DMAP). The amount of the hydrophilic organic solvent excluding the coalescent (D) is preferably small from the viewpoint of environmental load, and is preferably 0 to 20% by mass based on the total amount of the aqueous medium.

[0076] The aqueous polyurethane resin dispersion composition contains the polyurethane resin (A), the curing agent (B), the amine compound (C), the film-forming aid (D), and an aqueous medium, and may contain other resins and / or other additives as necessary.

[0077] Examples of the other resins include polyester resins, acrylic resins, polyether resins, polycarbonate resins, polyurethane resins, epoxy resins, alkyd resins, polyolefin resins, and vinyl chloride resins. Among these, polyester resins, acrylic resins, and polyolefin resins are preferred, and it is more preferred to add at least one selected from polyester resin emulsions, acrylic resin emulsions, and polyolefin resin emulsions, with acrylic resin emulsions being even more preferred. These may be used alone or in combination. The emulsion refers to a state in which a resin is dispersed in water or a mixed medium of an organic solvent and water.

[0078] Examples of the other additives that can be used include surface conditioners, emulsifiers, thickeners, fillers, foaming agents, pigments, dyes, oil repellents, hollow foams, flame retardants, antifoaming agents, leveling agents, antiblocking agents, ultraviolet absorbers, light stabilizers, plasticizers, anti-settling agents, etc. These additives may be used alone or in combination.

[0079] The surface conditioner can be any known surface conditioner, leveling agent, wetting agent, defoaming agent, or the like, as long as it has the ability to eliminate defects in the coating film that generally occur due to changes in viscosity, changes in surface tension, and the generation of bubbles that accompany an increase in molecular weight. Preferred examples of the surface conditioner include various surface conditioners, leveling agents, wetting agents, defoaming agents, and the like, such as acrylic, vinyl, silicone, fluorine, cellulose, natural wax, and water-soluble organic solvents, as well as surfactants, and among these, wetting agents are preferred.

[0080] The pigments may be any known color pigment, extender pigment, or luster pigment. Examples of color pigments include inorganic pigments such as iron oxide, titanium oxide, zinc oxide, molybdenum red, cobalt blue, and carbon black, and organic pigments such as quinacridone pigments, quinacridonequinone pigments, dioxazine pigments, phthalocyanine pigments, anthrapyrimidine pigments, anthanthrone pigments, indanthrone pigments, flavanthrone pigments, perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, and azo pigments. Examples of extender pigments include clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white. Examples of luster pigments include aluminum, copper, zinc, brass, nickel, aluminum oxide, mica, aluminum oxide coated with titanium oxide or iron oxide, and mica coated with iron oxide or titanium oxide.

[0081] <Production of aqueous polyurethane resin dispersion composition> The method for producing the aqueous polyurethane resin dispersion composition of the present invention is not particularly limited, and any known production method can be used. For example, the aqueous polyurethane resin dispersion composition can be produced by stirring and mixing the polyurethane resin (A), the curing agent (B), the amine compound (C), the film-forming aid (D), and the other additives.

[0082] <Uses of the aqueous polyurethane resin dispersion composition> The aqueous polyurethane resin dispersion composition of the present invention can be suitably used as a paint composition or a coating composition. The paint composition or coating composition is a composition containing the aqueous polyurethane resin dispersion that is used for paint applications or coating applications.

[0083] Aqueous dispersions and / or aqueous solutions of resins other than those contained in the aqueous polyurethane resin dispersion composition can be added to the paint composition or coating composition. The present invention can fully achieve the desired effects with only the above-mentioned urethane-related components, and focusing solely on the effect of reducing the burden on the manufacturing process, it is not necessarily necessary to include a separate step of polymerizing other monomer components such as acrylic monomers or to add other resins. However, other resins may be added to complement or supplement the properties of the paint or coating agent, such as the material of the substrate to be coated. Examples of such other resins include polyester resins, acrylic resins, polyether resins, polycarbonate resins, polyurethane resins, epoxy resins, alkyd resins, polyolefin resins, and vinyl chloride resins. These may be used alone or in combination. It is preferable that the other resins have one or more hydrophilic groups. Examples of hydrophilic groups include hydroxyl groups, carboxyl groups, sulfonic acid groups, and polyethylene glycol groups.

[0084] The other resin is preferably at least one selected from the group consisting of polyester resin, acrylic resin, and polyolefin resin, and more preferably at least one selected from the group consisting of polyester resin and polyolefin resin.

[0085] Polyester resins can usually be produced by an esterification reaction or transesterification reaction between an acid component and an alcohol component. The acid component can be a compound that is usually used as an acid component in the production of polyester resins. Examples of the acid component that can be used include aliphatic polybasic acids, alicyclic polybasic acids, and aromatic polybasic acids.

[0086] An acrylic resin is a compound having polymerization units derived from a (meth)acrylic monomer having one or more types of (meth)acryloyl groups in the molecule. Acrylic resins are usually obtained by polymerizing one or more types of (meth)acrylic monomers.

[0087] Examples of the (meth)acrylic monomer include 2-ethylhexyl (meth)acrylate, methyl (meth)acrylate, butyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, dodecyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, isobornyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, polyethylene glycol-polypropylene glycol mono(meth)acrylate, poly(ethylene glycol-tetramethylene glycol) mono(meth)acrylate, poly(propylene glycol-tetramethylene glycol) mono(meth)acrylate, (meth)acrylic acid alkyl esters such as octoxypolyethylene glycol-polypropylene glycol mono(meth)acrylate, lauroxypolyethylene glycol mono(meth)acrylate, and stearoxypolyethylene glycol mono(meth)acrylate; and (meth)acrylic acid aryl esters such as phenoxyethyl (meth)acrylate, nonylphenoxypolyethylene glycol mono(meth)acrylate, nonylphenoxypolypropylene glycol polyethylene glycol mono(meth)acrylate, phenoxypolyethylene glycol mono(meth)acrylate, and phenoxypolypropylene glycol polyethylene glycol mono(meth)acrylate.

[0088] Examples of polyether resins include polymers or copolymers having an ether bond, such as polyoxyethylene-based polyethers, polyoxypropylene-based polyethers, polyoxybutylene-based polyethers, and polyethers derived from aromatic polyhydroxy compounds such as bisphenol A or bisphenol F.

[0089] Polycarbonate resins include polymers produced from bisphenol compounds, such as bisphenol A polycarbonate.

[0090] Examples of polyurethane resins include resins having urethane bonds obtained by reacting various polyol components such as acrylic polyol, polyester polyol, polyether polyol, and polycarbonate polyol with polyisocyanate.

[0091] Examples of epoxy resins include resins obtained by reacting a bisphenol compound with epichlorohydrin, and examples of bisphenol compounds include bisphenol A and bisphenol F.

[0092] Examples of alkyd resins include alkyd resins obtained by reacting polybasic acids such as phthalic acid, terephthalic acid, and succinic acid with polyhydric alcohols and further with modifiers such as fats and oils, fatty acids (soybean oil, linseed oil, coconut oil, stearic acid, etc.), and natural resins (rosin, amber, etc.).

[0093] Examples of polyolefin resins include those obtained by polymerizing or copolymerizing an olefinic monomer with other monomers according to a conventional polymerization method, dispersing the resulting polyolefin resin in water using an emulsifier, or those obtained by emulsion polymerizing an olefinic monomer with other monomers. In some cases, so-called chlorinated polyolefin-modified resins obtained by chlorinating the above-mentioned polyolefin resins may also be used.

[0094] Examples of olefin-based monomers include α-olefins such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-decene, and 1-dodecene; and conjugated or non-conjugated dienes such as butadiene, ethylidene norbornene, dicyclopentadiene, and 1,5-hexadiene. These monomers may be used alone or in combination.

[0095] Examples of other monomers copolymerizable with the olefin-based monomer include styrene, vinyl acetate, vinyl alcohol, maleic acid, citraconic acid, itaconic acid, maleic anhydride, citraconic anhydride, and itaconic anhydride. These monomers may be used alone or in combination.

[0096] The paint composition and coating composition may contain, as necessary, conventional additives such as surface conditioners, emulsifiers, curing agents, thickeners, fillers, foaming agents, pigments, dyes, oil repellents, hollow foams, flame retardants, antifoaming agents, leveling agents, antiblocking agents, ultraviolet absorbers, light stabilizers, plasticizers, anti-settling agents, etc. A plurality of these may be used in combination.

[0097] The method for producing the paint composition and the coating composition is not particularly limited, and known production methods can be used. Generally, the paint composition and the coating composition are produced by mixing the aqueous polyurethane resin dispersion composition with the other resins and / or various additives described above, adding an aqueous medium, and adjusting the viscosity according to the application method.

[0098] Examples of materials to which the paint composition or the coating composition can be applied include metals, plastics, inorganic materials, wood, and electrodeposition-coated panels. The composition can be used to coat a wide range of items, including various flooring materials, metal products, and rubber products. Therefore, one aspect of the present invention relates to a floor coating, plastic coating, steel plate treatment, primer (e.g., for metal exteriors), or base coating containing the polyurethane resin dispersion composition. Another aspect of the present invention relates to the use of a coating film obtained from the polyurethane resin dispersion composition as a floor coating, plastic coating, rubber coating, steel plate treatment, or metal exterior primer or base coating.

[0099] Examples of methods for applying a paint composition or a coating agent composition include bell coating, spray coating, roll coating, shower coating, and dip coating. Furthermore, after painting or coating, other materials can be applied to the painted or coated surface. Examples of methods for applying such intermediate coating compositions include inkjet printing, flexographic printing, gravure printing, reverse offset printing, sheet-fed screen printing, rotary screen printing, air spray coating, bell coating, and electrostatic coating.

[0100] <Coating film> A coating film can be obtained by drying the aqueous polyurethane resin dispersion composition of the present invention. The thickness of the coating film obtained from the aqueous polyurethane resin dispersion composition is not particularly limited, but is preferably adjusted to 0.5 to 200 μm, more preferably adjusted to 1 to 100 μm, even more preferably adjusted to 5 to 50 μm, and even more preferably adjusted to 10 to 40 μm.

[0101] The alcohol resistance of the coating film obtained from the aqueous polyurethane resin dispersion composition of the present invention, as measured by the method described in the Examples, is preferably 18 or more reciprocating rubs, and more preferably 25 or more reciprocating rubs, until the coating film breaks. The alcohol resistance is measured by the method described in the Examples.

[0102] <Coating film manufacturing method> A coating film can be obtained by applying the aqueous polyurethane resin dispersion composition of the present invention and then drying or curing it. One aspect of the present invention relates to a method for producing a coating film, which includes a step of applying the aqueous polyurethane resin dispersion composition and then drying it. After applying the paint composition or coating composition to the substrate, it is preferable to dry or cure the composition by heating to obtain a coating film. Examples of the heating method include a heating method using the heat of reaction of the composition itself, and a heating method in which the paint composition or coating composition and the material to which it is applied are actively heated. Examples of active heating include a method in which the paint composition or coating composition and the material to which it is applied are placed in a hot air oven, an electric furnace, or an infrared induction heating furnace and heated.

[0103] For example, the coating composition of the present invention can be dried or cured by heating to a temperature of 20°C or higher and preferably 100°C or lower, more preferably 80°C or lower. Specifically, the coating composition can be applied to various plastic substrates such as electrodeposition coated surfaces, steel plates, wood, rubber, polycarbonate resin, acrylic resin, polyethylene terephthalate (PET) resin, and acrylonitrile butadiene styrene (ABS) resin using a spray, brush, applicator, bar coater, or the like, and then cured by holding the composition in an oven, heating tank, or the like at 100°C or less, preferably 80°C or less, for 1 to 120 minutes, preferably 1 to 100 minutes, and more preferably 1 to 60 minutes.

[0104] When used as a primer, base coat, etc. in a multi-layer coating film, after application to the various substrates mentioned above, it can be held, for example, at 20 to 80°C for 1 to 30 minutes, preferably 1 to 10 minutes, more preferably 2 to 6 minutes, and then, as an optional component, another type of base coat can be applied and treated at the same temperature and time, after which a top coat (sometimes called a clear coat) can be applied and heated at 100°C or less, preferably 80°C or less, for 10 to 120 minutes, more preferably 20 to 90 minutes, and even more preferably 30 to 60 minutes. [Example]

[0105] Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these.

[0106] [Production of aqueous polyurethane resin dispersion composition] (Production of aqueous polyurethane resin dispersion) [Synthesis Example 1] Water-based polyurethane resin dispersion (U1) Polycarbonate polyol (ETERNACOLL® UM90 (3 / 1) (manufactured by Ube Industries, Ltd.; number average molecular weight: 916; hydroxyl value: 123 mg KOH / g; polycarbonate diol, 190 g, obtained by reacting a polyol mixture with a 3:1 molar ratio of 1,4-cyclohexanedimethanol:1,6-hexanediol with a carbonate ester)), 2,2-dimethylolpropionic acid (26.0 g), and hydrogenated MDI (174 g) were heated in dipropylene glycol dimethyl ether (DMM, 136 g) in the presence of dibutyltin dilaurate (0.3 g) under a nitrogen atmosphere at 80 to 95°C for 5 hours. The reaction mixture was cooled to 80°C, and triethylamine (19.6 g) was added and mixed. 400 g of the resulting mixture was added to water (563 g) with vigorous stirring. Next, a 35% by mass aqueous solution of 2-methyl-1,5-pentanediamine (60.4 g) was added to obtain an aqueous polyurethane resin dispersion (U1). The solid content was 30% by mass. In the aqueous polyurethane resin dispersion (U1), the content of the alicyclic structure contained in the polyurethane resin was 43.5% by mass on a solids basis relative to the total amount of polyurethane resin.

[0107] [Synthesis Example 2] Water-based polyurethane resin dispersion (U2) Polycarbonate polyol (ETERNACOLL® UM90(1 / 3) (manufactured by Ube Industries, Ltd.; number average molecular weight: 916; hydroxyl value: 123 mgKOH / g; polycarbonate diol, 190 g, obtained by reacting a polyol mixture with a 1:3 molar ratio of 1,4-cyclohexanedimethanol:1,6-hexanediol with a carbonate ester)), 2,2-dimethylolpropionic acid (26.0 g), and hydrogenated MDI (174 g) were heated in dipropylene glycol dimethyl ether (DMM, 136 g) in the presence of dibutyltin dilaurate (0.3 g) under a nitrogen atmosphere at 80 to 95°C for 5 hours. The reaction mixture was cooled to 80°C, and triethylamine (19.6 g) was added and mixed. 400 g of the resulting mixture was added to water (563 g) with vigorous stirring. Next, a 35% by mass aqueous solution of 2-methyl-1,5-pentanediamine (60.4 g) was added to obtain an aqueous polyurethane resin dispersion (U2). The solid content was 30% by mass. In the aqueous polyurethane resin dispersion (U2), the content of the alicyclic structure contained in the polyurethane resin was 32.3% by mass on a solids basis relative to the total amount of polyurethane resin.

[0108] [Synthesis Example 3] Water-based polyurethane resin dispersion (U3) Polycarbonate polyol (ETERNACOLL (registered trademark) UM90 (3 / 1) (manufactured by Ube Industries, Ltd.; number average molecular weight 916; hydroxyl value 123 mgKOH / g; polycarbonate diol obtained by reacting a polyol mixture in which the polyol component was a 3:1 molar ratio of 1,4-cyclohexanedimethanol:1,6-hexanediol with a carbonate ester, 190 g), 2,2-dimethylolpropionic acid (27.4 g), and hydrogenated MDI (178 g) were heated in dipropylene glycol dimethyl ether (DMM, 141 g) in the presence of dibutyltin dilaurate (0.3 g) under a nitrogen atmosphere at 80 to 95°C for 5 hours. The reaction mixture was heated at 80°C. The mixture was cooled to °C, and triethylamine (20.7 g) was added and mixed. 418 g of the resulting mixture was added to water (581 g) with strong stirring. Next, a 35 mass% aqueous solution of 2-methyl-1,5-pentanediamine (44.6 g) and a 35 mass% aqueous solution of 2-(2-aminoethylamino)ethanol (16.8 g) were added to obtain aqueous polyurethane resin dispersion (U3). The solids content was 30 mass%. In aqueous polyurethane resin dispersion (U3), the content of alicyclic structures in the polyurethane resin was 43.6 mass% on a solids basis relative to the total amount of polyurethane resin.

[0109] [Synthesis Example 4] Water-based polyurethane resin dispersion (U4) Polycarbonate polyol (ETERNACOLL® UM90 (3 / 1) (manufactured by Ube Industries, Ltd.; number average molecular weight: 916; hydroxyl value: 123 mg KOH / g; polycarbonate diol, 190 g, obtained by reacting a polyol mixture with a 3:1 molar ratio of 1,4-cyclohexanedimethanol:1,6-hexanediol with a carbonate ester)), 2,2-dimethylolpropionic acid (27.4 g), and hydrogenated MDI (178 g) were heated in N-ethylpyrrolidone (NEP, 141 g) in the presence of dibutyltin dilaurate (0.3 g) under a nitrogen atmosphere at 80 to 95°C for 5 hours. The reaction mixture was cooled to 80°C, and triethylamine (20.7 g) was added and mixed. 418 g of the resulting mixture was added to water (581 g) with vigorous stirring. Next, 35% by mass of 2-methyl-1,5-pentanediamine aqueous solution (44.6 g) and 35% by mass of 2-(2-aminoethylamino)ethanol aqueous solution (16.8 g) were added to obtain aqueous polyurethane resin dispersion (U4). The solid content was 30% by mass. In aqueous polyurethane resin dispersion (U4), the content of alicyclic structures contained in the polyurethane resin was 43.6% by mass on a solids basis relative to the total amount of polyurethane resin.

[0110] [Synthesis Example 5] Water-based polyurethane resin dispersion (U5) Polycarbonate polyol (ETERNACOLL® UH200 (manufactured by Ube Industries, Ltd.; number average molecular weight 2,000; hydroxyl value 57 mgKOH / g; polycarbonate diol obtained by reacting 1,6-hexanediol with a carbonate ester, 276 g)), 2,2-dimethylolpropionic acid (18.2 g), and hydrogenated MDI (108 g) were heated in dipropylene glycol dimethyl ether (DMM, 134 g) in the presence of dibutyltin dilaurate (0.3 g) under a nitrogen atmosphere at 80 to 95°C for 5 hours. The reaction mixture was cooled to 80°C, and triethylamine (13.7 g) was added and mixed. 395 g of the mixture was then added to water (574 g) with vigorous stirring. Next, a 35% by mass aqueous solution of 2-methyl-1,5-pentanediamine (31.0 g) was added to obtain an aqueous polyurethane resin dispersion (U5). The solid content was 30% by mass. In the aqueous polyurethane resin dispersion (U5), the content of the alicyclic structure contained in the polyurethane resin was 16.2% by mass on a solids basis relative to the total amount of polyurethane resin.

[0111] (Hardening agent (B)) The following curing agents (B) were used. The abbreviations in Table 1 are as follows: H1: Vencorex EASAQUA L600 (linear aliphatic isocyanate curing agent, solid content 97% by mass) H2: Vencorex EASAQUA XD870 (alicyclic isocyanate curing agent, solid content 70% by mass) H3: Carbodilite E-05 (carbodiimide curing agent, solid content 42% by mass) manufactured by Nisshinbo Chemical Inc.

[0112] [Example 1] An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 0.09 parts by mass of triethylenediamine, 5.0 parts by mass of N-ethylpyrrolidone, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U1.

[0113] [Example 2] An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 1, except that the aqueous polyurethane resin dispersion U2 was used instead of the aqueous polyurethane resin dispersion U1.

[0114] [Example 3] An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 1, except that the aqueous polyurethane resin dispersion U3 was used instead of the aqueous polyurethane resin dispersion U1.

[0115] [Example 4] An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 3, except that 9.2 parts by mass of the isocyanate curing agent H2 was used per 100 parts by mass of the aqueous polyurethane resin dispersion U3.

[0116] [Example 5] An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 3, except that 0.6 parts by mass of triethylenediamine was used per 100 parts by mass of the aqueous polyurethane resin dispersion U3.

[0117] [Example 6] An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 3, except that 0.06 parts by mass of triethylenediamine was used per 100 parts by mass of the aqueous polyurethane resin dispersion U3.

[0118] [Example 7] An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 3, except that 5.0 parts by mass of 1,3-dimethyl-2-imidazolidinone (DMI) was used instead of N-ethylpyrrolidone per 100 parts by mass of the aqueous polyurethane resin dispersion U3.

[0119] [Example 8] An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 3, except that 3.0 parts by mass of N-ethylpyrrolidone was used per 100 parts by mass of the aqueous polyurethane resin dispersion U3.

[0120] [Example 9] An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 0.09 parts by mass of triethylenediamine, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U4.

[0121] [Example 10] An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 0.09 parts by mass of triethylenediamine, 5.0 parts by mass of N-ethylpyrrolidone, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U5.

[0122] [Comparative Example 1] An aqueous polyurethane resin dispersion composition was produced by blending 12.5 parts by mass of purified water, 0.09 parts by mass of triethylenediamine, 5.0 parts by mass of N-ethylpyrrolidone, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U1.

[0123] Comparative Example 2 An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 1, except that 10.0 parts by mass of carbodiimide curing agent H3 was used instead of isocyanate curing agent H1 per 100 parts by mass of aqueous polyurethane resin dispersion U1.

[0124] Comparative Example 3 An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 5.0 parts by mass of N-ethylpyrrolidone, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U1.

[0125] Comparative Example 4 An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 0.09 parts by mass of triethylenediamine, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U1.

[0126] Comparative Example 5 An aqueous polyurethane resin dispersion composition was produced in the same manner as in Example 1, except that 5.0 parts by mass of methyl ethyl ketone (MEK) was used instead of N-ethylpyrrolidone per 100 parts by mass of the aqueous polyurethane resin dispersion U1.

[0127] [Manufacturing method of test sample] For the evaluation tests described below, test specimens were prepared by the following method: Each of the aqueous polyurethane resin dispersion compositions of Examples 1 to 10 and Comparative Examples 1 to 5 was applied to a polycarbonate plate (70 mm × 150 mm, 2.0 mm thick, manufactured by Engineering Test Service Co., Ltd.) using a #18 bar coater, heated at 70°C for 60 minutes, and allowed to stand at 23°C for 24 hours to obtain test samples in which a coating film was formed on the polycarbonate plate.

[0128] [Evaluation of alcohol resistance] The obtained test samples were subjected to an ethanol rubbing test to evaluate their alcohol resistance. The ethanol rubbing test was performed by rubbing the surface of each test sample back and forth with a 700g load on a wafer soaked in 99.5% ethanol, and measuring the number of reciprocating strokes until breakage of the coating was confirmed. The higher the number of reciprocating strokes, the higher the alcohol resistance.

[0129] [Table 1]

[0130] The results in Table 1 show that all Examples had good alcohol resistance in the ethanol rubbing test. Specifically, even when the content of the alicyclic structure in the polycarbonate polyol (Aa) having an alicyclic structure was changed as in Examples 1 and 2, good alcohol resistance was exhibited, with particularly high alcohol resistance being exhibited at 20% by mass or more. Furthermore, polyurethane resins (A) having hydroxyl groups as shown in Examples 3 to 9 exhibited even better alcohol resistance. Furthermore, Examples 3 and 4 show that linear aliphatic isocyanate curing agents (B) exhibit particularly good alcohol resistance. Furthermore, even when the content of the amine compound catalyst (C) relative to the polyurethane resin (A) was changed within the range of Examples 3, 5, and 6, good alcohol resistance was exhibited, with particularly high alcohol resistance being exhibited at 0.30% by mass or more. Furthermore, Examples 3 and 7 show that particularly good alcohol resistance was exhibited when the film-forming aid (D) was a pyrrolidone compound. In addition, even when the content of the coalescent (D) relative to the polyurethane resin (A) was varied within the ranges of Examples 3, 8, and 9, excellent alcohol resistance was observed, with particularly high alcohol resistance being observed at 15% by mass or higher. Alicyclic structures generally have the effect of increasing coating film strength, but Example 10 demonstrates that even polyurethane resin dispersions containing a relatively low proportion of alicyclic structures exhibit alcohol resistance. Meanwhile, Comparative Examples 1 and 2 demonstrate that alcohol resistance is reduced when the aqueous polyurethane resin dispersion composition does not contain an isocyanate curing agent (B). Comparative Example 3 demonstrates that alcohol resistance is reduced when the aqueous polyurethane resin dispersion composition does not contain an amine compound (C). Comparative Examples 4 and 5 demonstrate that alcohol resistance is reduced when the aqueous polyurethane resin dispersion composition does not contain a pyrrolidone compound or a cyclic urea compound as the coalescent (D).

[0131] [Reference example 1] An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U3.

[0132] [Reference example 2] An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 0.6 parts by mass of triethylenediamine, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U3.

[0133] [Reference example 3] An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 0.5 parts by mass of 2-(dimethylamino)ethanol, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U3.

[0134] [Reference example 4] An aqueous polyurethane resin dispersion composition was produced by blending 5.6 parts by mass of isocyanate curing agent H1, 12.5 parts by mass of purified water, 0.6 parts by mass of 2-(dimethylamino)-2-methyl-1-propanol, 4.5 parts by mass of red pigment (EMF Pink 2B-1 manufactured by Toyocolor Co., Ltd.), and 0.6 parts by mass of surface conditioner (BYK-Chemie; BYK-345) with 100 parts by mass of aqueous polyurethane resin dispersion U3.

[0135] [Manufacturing method of test sample] For the evaluation tests described below, test specimens were prepared by the following method: Each of the aqueous polyurethane resin dispersion compositions of Reference Examples 1 to 4 was applied to a polycarbonate plate (70 mm × 150 mm, 2.0 mm thick, manufactured by Engineering Test Service Co., Ltd.) using a #18 bar coater, heated at 70°C for 60 minutes, and left to stand at 23°C for 24 hours to obtain test samples in which a coating film was formed on the polycarbonate plate.

[0136] [Evaluation of alcohol resistance] The obtained test samples were subjected to an ethanol rubbing test to evaluate their alcohol resistance. The ethanol rubbing test was performed by rubbing the surface of each test sample back and forth with a 700g load on a wafer soaked in 99.5% ethanol, and measuring the number of reciprocating strokes until breakage of the coating was confirmed. The higher the number of reciprocating strokes, the higher the alcohol resistance.

[0137] [Table 2]

[0138] The results in Table 2 show that tertiary amine compounds having active hydrogen do not contribute to improving alcohol resistance, while tertiary amine compounds having no active hydrogen do improve alcohol resistance. [Industrial Applicability]

[0139] The aqueous polyurethane resin dispersion composition of the present invention has excellent alcohol resistance and can be widely used as a paint composition, a coating composition, etc.

Claims

1. An aqueous polyurethane resin dispersion composition comprising a polyurethane resin (A), a curing agent (B), an amine compound (C), a coalescent (D), and an aqueous medium, the curing agent (B) is a polyisocyanate compound, the amine compound (C) has a boiling point of 100°C or higher and is an amine compound having no active hydrogen (excluding tertiary amide compounds), The aqueous polyurethane resin dispersion composition, wherein the coalescent (D) is at least one selected from the group consisting of cyclic amide compounds and cyclic urea compounds.

2. 2. The aqueous polyurethane resin dispersion composition according to claim 1, wherein a main chain of the polyurethane resin (A) has a structure derived from a polycarbonate polyol (Aa) having an alicyclic structure, a structure derived from a polyisocyanate (Ab), and a structure derived from an acidic group-containing polyol (Ac).

3. The aqueous polyurethane resin dispersion composition according to claim 2, wherein the content of the alicyclic structure in the polycarbonate polyol (Aa) having an alicyclic structure is 20 to 50 mass% based on the total amount of the polycarbonate polyol (Aa).

4. 4. The aqueous polyurethane resin dispersion composition according to claim 1, wherein the content of the alicyclic structure in the polyurethane resin (A) is 20 to 70 mass% based on the solid content.

5. The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 4, wherein the polyurethane resin (A) has a hydroxyl value of 3.0 to 15 mgKOH / g.

6. The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 5, wherein the curing agent (B) is a linear aliphatic polyisocyanate compound.

7. The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 6, wherein the amine compound (C) is a heterocyclic aliphatic tertiary amine compound.

8. The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 7, wherein the amine compound (C) is contained in an amount of 0.30 to 3.0% by mass relative to the polyurethane resin (A).

9. The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 8, wherein the coalescent (D) is a pyrrolidone compound.

10. The aqueous polyurethane resin dispersion composition according to any one of claims 1 to 9, wherein the film-forming aid (D) is contained in an amount of 15 to 40% by mass relative to the polyurethane resin (A).

11. A coating composition comprising the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10.

12. A coating composition comprising the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10.

13. A floor coating agent comprising the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10.

14. A plastic coating agent comprising the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10.

15. A steel plate treatment agent comprising the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10.

16. A primer comprising the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10.

17. A base coating agent comprising the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10.

18. A method for producing a coating film, comprising a step of applying the aqueous polyurethane resin dispersion composition according to any one of claims 1 to 10 and then drying it.

19. The method for producing a coating film according to claim 18, wherein the drying is carried out at 20 to 100°C.

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